With advancement of the display technology, electroluminescent display panels have gradually become one of the hotspots in the research field of flat panel display panels at present, and more and more active matrix organic light emitting diode (AMOLED) displays have entered the market. As compared with a conventional thin film transistor-liquid crystal display (TFT-LCD), an AMOLED display has a faster response speed, a higher contrast ratio, and a wider viewing angle.
A circuit structure of a typical AMOLED pixel circuit, as shown in FIG. 1, includes: a drive transistor m1, a switch transistor m2, a storage capacitor c, and an organic light-emitting diode OLED; a gate electrode of the drive transistor m1 is respectively connected with a drain electrode of the switch transistor m2 and one terminal of the storage capacitor c, a source electrode of the drive transistor m1 is connected with an anode of the organic light-emitting diode OLED, and a drain electrode of the drive transistor m1 is respectively connected with the other terminal of the storage capacitor c and a high-level signal terminal VDD; a gate electrode of the switch transistor m2 is connected with a gate signal terminal Gate line, a source electrode of the switch transistor m2 is connected with a data signal terminal Data line; and a cathode of the organic light-emitting diode OLED is connected with a low-level signal terminal VSS.
FIG. 2 is a working timing diagram of the pixel circuit shown in FIG. 1 within display time of one frame. It may be known from FIG. 2 that, during a time period t1, the gate signal terminal Gate line inputs a high-level signal, and the switch transistor m2 is turned on, at which time a data signal on the data signal terminal Data line is written to the storage capacitor c and the gate electrode of the drive transistor m1, so that the drive transistor m1 is turned on, and the organic light-emitting diode OLED starts to work and emit light; during a time period t2, the gate signal terminal Gate line inputs a low-level signal, and the switch transistor m2 is turned off, at which time, due to an electric discharge effect of the storage capacitor c, the gate electrode of the drive transistor m1 maintains a high-level state, the drive transistor m1 continues to be turned on, and the organic light-emitting diode OLED continues to work and emit light until a data signal for displaying a next frame is input, therefore ensuring the continuity of a display picture.
However, when the AMOLED displays a fixed-grayscale static picture within display time of multiple frames, the pixel circuit shown in FIG. 1 needs to repeatedly refresh the data signal on the data signal terminal Data line within display time of each frame, which results in large power consumption of the pixel circuit.